Pulverizing-mill



J. W. FULLER.

PULVERIZING MILL. APPLICATION FILED AUG-27, 191?.

1,358,837. Patented Nov. 16, 1920.

2 SHEETS-SHEET i.

M 351; whine S J. W. FULLER.

PULVERIZING MILL, APPLICATION FILED AUG.27, 1911 JAMES W. FULLER, 0F CATASAUQUA, PENNSYLVANIA.

PULVERIZING-MILL.

Specification of Letters Patent.

Patented Nov. 16, 1920.

Application filed August 27, 1917. Seria1 No. 188,387.

' make and use the same.

The present invention relates to pulverizing mills and more particularly to a mill adapted for pulverizing material preliminary to feeding it to a second mill in which a final pulverizing of the material is to take place.

The invention is herein shown as applied to a Fuller pulverizing mill of the' type shown, for example, in my United States Patent Nos. 849,779, 922,468 and 1,039,721. Pulverizing mills of that type have a pulverizing zone containing a race-way within which operates the pulverizing balls actuated by a series of rotating radial pushers, and the pulverized material is removed upwardly from the pulverizing zone largely by the suction of rotating lifting blades which lift the finer pulverized material into the field of a superjacent series of fan blades which float it against and through the cylindrical screen surrounding the upper part of the pulverizing chamber. In accordance with the present invention, I provide, as a supplement to these lifting blades, acting above the pulverizing zone and withdrawing the material upwardly therefrom largely by suction, a series of lifting scoops located and acting. immediately in the pulverizing zone, so that substantially all of the material in the pulverizing zone is subjected to the positive lifting action of these scoops, and thereby the larger particles, which would not be lifted by the suction of the lifting blades, are now raised, together with all of the finer material, directly into the field of action of the lifting blades. In this way the relatively coarse material which it is intended the preliminary mill shall deliver is effectively and economically presented to the screening fans and the output of the mill is thereby largely increased.

It is customary, in machines of this type, to provide in the pulverizing zone a series of pulverizing balls spaced apart and actuated by pushers, and I find that for preliminary grinding the output of such a mill may be very largely increased by removing alternate balls, with their actuating pushers, and substituting for these removed balls and pushers the lifting scoops above re ferred to.

The particular nature of the invention will appear more clearly from a detailed description of a preferred embodiment illustrated in the accompanying drawings, in which Figure 1 is a view in sectional elevation of the mill; Fig. 2 is a View in elevation of the rotating mechanism of the mill and Fig. 3 is a top plan view of the mechanism shown in Fig. 2.

Referring to the drawings in which similar reference characters denote similar parts throughout the several views, 10 represents the base of the machine and 11 a standard upon the top of which is a casing 12 surrounding the grinding mechanism. On top of the casing 12 is a frame 13 supporting a screen 14 and having at its top a removable cover plate 15. provided with a bearing member 16 which may be of any desired construction. In this bearing member is a vertical shaft 17'supported at its foot in a bearing 18 set in a recess in the base 10. The shaft is also guided at the point 19 by the top portion 20 of the standard 11. The plate 15 is provided with an aperture 21 through which material may be supplied from a feeding device 22. The shaft 17 is provided with a driving pulley 23 lying within the support 11. Supported in the interior of the casing 12 is an annular concave grinding ring 24 and between this ring and the outer wall of the casing 12 is an annular passageway 25 opening at its upper end just outside of the screen 14-and at its lower end opening into a chamber 26 from which pulverized material may be removed through a spout 27.

The rotating portions of the apparatus are supported upon the shaft 17 and comprise a carrier 30 for holding the grinding balls 31 and a frame or yoke 32 supported upon the keyed to the shaft 17 as at 33. The frame 32 is provided with outwardly extending arms 34 having vertical extensions 35 to which is attached a ring 36 composed of upper and lower portions connected together by strips or bands 37 so as to provide large apertures in the sides of the ring. Attached to'the lower portion of the ring upper end of the carrier 30 and are inclined lifting blades 38 which are upwardly turned at their'lower outer edges as the ring 36 are brackets 40' which support fanning blades 41.

shown there are four of these fannlng In the embodiment here blades arranged symmetrically about the ring 36 and each one occupying a position intermediate the blades 38 and overlapping the same for a short distance.

At the bottom of the frame or yoke 32 are a number of radial projections or arms 42.

In the embodiment here shown there are.

four of these projections arranged symmetrically about the axis of the machine. Each of the projections is provided with an aperture '43. In the embodiment here shown two of the projections carry pusher members 44 which may be detachably secured to the projections by means of pins or bolts passing through the apertures 43. Each usher member is provided with a curved ace 45 adapted to engage one of the grinding balls 31. The other two projections. 42 carry I and will then fall through the rial is scoops 46. Each of these scoops comprises a body portion 47, which may be connected to-the projection 42 by downwardly and forward shaped portion 48 which in or bolt,-and a y extending scoopmay be given any desired form and curvature to produce the proper lifting effect. While in the embodiment here shown'there are twdpushers and two scoops arranged alternately and symmetrically about the framelor yoke 32, it will be understood that the invention is not limited to any particular number or arrangement of these members but the symmetrical arrangement is preferred as it produces the] most perfect balance in the moving parts of the apparatus. To aid in removing material from the chamber 26, a platform 49 may be attached to the shaft 17 so that its outer portion rotates through the base of the chamber 26.

In the operation of ,the apparatus, the

shaft and moving parts are driven by a belt desired mategradually fed into the machine through aperture 21. The screen 14 will be of a mesh such as to permit the passage therethrough of particles of the intended size for the preliminary grinding. If in the material supplied to the upper portion of the machine there are particles small enough to pass through the mesh of the screen, these particles will be driven out by the fanning blades 41 andcaught by the outer wall 13 passageway 25 into the chamber 26 from which their removal will be assisted by the rotating platform 49. Some of the smaller particles may fall beneath the region of the fanning blades passing over :pull'ey 23 and the 41 in which they will be caught by the oblique blades 38 and driven the region of the fanning blades and will ultimately 'be driven through the screen by the farming blades. The particles that are too large to pass through the screen will fall into the pulverizing zone between the grinding ring and the balls where they will be ground to smaller size. .The ground material Will be elevated from the zone of operation of the grinding balls by the scoops or plows 46 and fed directly into the zone of the lifting blades 38 and the upward current of air produced within the interior of the machine. The oblique or inclined lifting blades 38 will then lift the material into the regionof the fanning blades 41 which will force as much of the inaterial as has been ground to the required degree of fineness through the screen 14 after which it will be discharged from the apparatus. If any of the material lifted out of the grinding zone by the scoops 46 is still too coarse to pass through the screen 14 it will finally fall again into the grinding zone and be subjected to another pulverizing operation.

In the usual types of pulverizing machines intended for the final grinding of material, the suction effect produced in the upper or separating chamber is usually depended upon to lift material out of the grinding zone. In the apparatus' of the present invention the scoops 46 mechanically lift the material out of the region of the grinding balls and convey it upwardly into the region of the inclined lifting blades 38 by which it is fed to the fanning blades 41.

By the provision ofthese lifting means the preliminary grinding of material may be performed in considerably less time than is the case where the suction effect is depended upon for lifting the material out of the grinding'zone. The capacity of the mill is" therefore materially increased and the material is supplied to' the pulverizer which is to be used for the final grinding operation in a partially ground condition upwardly into which permits the final grinding operation of construction of the apparatus may be made without departing from the principle of the invention.

I claim:

1. In a pulverizing mill, a pulverizing zone containing a fixed grinding ring, a plurality of freely movable grindingballs, means for propellingthe balls in the ring, means above the pulverizing zone and movable with the propelling means for discharging material from the 'mill, and means associated with the propelling means and movable within I the pulverizing zone for lifting material from this zone into the zone of action of the discharging means.

2. In a pulverizing mill, a pulverizing zone containing a fixed grinding ring, a plu- 'rality of freely movable grinding balls,

means for propelling the balls in the ring, means above the pulverizing zone and movable with the propelling means for discharging material from the mill, and members associated with the propelling means and lying in the grinding zone and having front faces extending downwardly and forwardly from the tops of the members for lifting material from this zone into the ,zone of action of the discharging means.

3. In a pulverizing mill, a pulverizing zone containing a race-way, a series of r0- tatably mounted arms extending radially into the grinding zone, grinding balls in the race-way adapted to be propelled by alternate arms, and scoop members mounted on the other alternate arms for lifting the ground material out of the pulverizing zone.

4 In a pulverizing mill, a pulverizing zone containing a race-way, grinding balls, rotating pushers for moving the grinding balls in the race-way, and lifting devices adapted to rotate within the race-way for lifting the material out of the pulverizing zone, in combination with a superjacent series of lifting blades for further elevating the ground material, a screen, and fanning blades above the lifting blades for throwing the ground material against the screen.

5. In a pulverizing mill, a pulverizing zone containing a race-way, grinding balls in the race-way, rotatable pushers for actuating the grinding balls, and lifting devices adapted to rotate within the race-way for lifting the ground material out of'the pulverizing zone, in combination with a screen and means above the grinding zone for throwing the ground material radially against the screen.

6. In a pulverizing mill, a pulverizing zone containing a race-way, grinding balls in the race-way, a series of arms rotatably mounted and extending radially into the grinding zone, pushers inounted on alter nate arms and actuating said balls, and lifting scoops mounted on the other alternate arms to lift the ground material out of the pulverizing zone.

7 The combination in a pulverizer, of a frame; a fixed grinding ring; an annular screen above the grinding ring; a vertical, driven shaft; a yoke on the shaft; loose grinding balls arranged to be driven by the yoke and to travel in contact with the ring; and scoops alternating with the balls, which act to lift the pulverized material from the grinding ring and to discharge it over the succeeding ball, the lighter particles of material being carried to the screen and the heavier particles falling back over the balls onto the grinding ring.

8. The combination in a pulverizer, of a frame; a fixed grinding ring; an annular screen above the ring; a vertical, driven shaft; a yoke carried by said shaft having four arms; pushers carried by two of said arms; a ball in front of each pusher; a scoop member attached to each of the other two arms and alternating with the balls so that as the shaft rotates the balls will act in conjunction with the ring to pulverize the material and the scoops will lift the pulverized material from the grinding ring and will discharge it over the balls, the fine particles being carried to the screen while the other particles will drop into the path of the balls.

9. The combination in a pulverizer, of a frame; an annular grinding ring; an annular screen located above the grinding ring; a vertical, driven shaft; a yoke carried by the shaft; arms on the yoke; pushers mounted on alternate arms; balls located in advance of the pushers and arranged to be propelled over the grinding ring by said pushers; scoop members attached to the other arms of the yoke and alternating with the balls and arranged to lift the pulverized material from the ring; and blades secured to the upper portion of the yoke in line with the screen and arranged to throw the particles of material, lifted by the scoops, against the screen.

10. In a pulverizing mill a fixed grinding ring, grinding balls in the ring, means for propelling the balls in the ring, and members movable through the zone of action of the balls and having front faces extending downwardly and forwardly from the tops of the members for lifting material out of the zone.

11. A pulverizing mill comprising a casing, a grinding ring at the bottom of the casing, grinding balls in the ring, means at the top of the casingfor discharging pulverized material therefrom, scoop members within the grinding ring for liftingmaterial out of the zone of action of the balls,

and means lying between the grinding balls and the discharging means for lifting material into the zone of action of the last named means after it has been lifted out of the zone of action of the balls by the scoop members.

In testimony whereof I affix my signature.

' JAMES W. FULLER. 

